Fig 1.
Distribution of hydrocarbons in igneous rocks after Petford and McCaffrey [12].
The figure is similar but not identical to the original image and is used for illustrative purposes only.
Fig 2.
a) Geological map of Yemen showing the Sab’atayn basin (redrawn by the authors), and b) well location map of Habban field-block S2 indicating the inline and crossline seismic sections that are used in the study.
Fig 3.
Generalized stratigraphic column of Sab’atayn Basin modified after As-Saruri and Sorkhabi and Tari et al. [27,28].
The stratigraphic units and tectonic events are following Beydoun et al. and Casto [26,29]. Stratigraphic units are correlated with seismic facies through 2D seismic section taken from the present study (middle part of inline 1735, see Fig 2b for location). The figure is similar but not identical to the original image and is used for illustrative purposes only.
Fig 4.
a) 2D interpreted inline seismic section 1235, and b) 2D interpreted inline seismic section 1345.
The intrusion of the Sab’atayn salt is well seen in the western side of inline section 1235 associated with basement reservoir uplift.
Fig 5.
a) 2D interpreted inline seismic section 1445, and b) 2D interpreted inline seismic section 1495.
The uplift of Habban North Horst (HNH) is well developed in the right side of inline section 1495. The uplift bounding faults die at the top of Nayfa Formation.
Fig 6.
a) 2D interpreted inline seismic section 1695, and b) 2D interpreted inline seismic section 1835.
The uplift of (Habban Central Horst, HCH) is well developed in the middle of inline section 1835. The uplift bounding faults reach the top of Qishn Formation. A typical cylindrical intrusion of the Sab’atayn diaper reaches the near surface shallower strata left of inline section 1695.
Fig 7.
a) 2D interpreted crossline seismic section 221, and b) 2D interpreted crossline seismic section 391.
The intrusion of the Sab’atayn salt is well seen in both sections. The faulted-basement reservoir blocks and parts of the overlying Madbi Formation are juxtaposed along fault plans.
Fig 8.
a) 2D interpreted crossline seismic section 581, and b) 2D interpreted crossline seismic section 701.
One strong uplift is indicated in the right side of crossline section 581. Most of the faults effecting the basement reservoir die out at the Lam Member of Madbi Formation. Extensive faulting is indicated in the overlying section of the Late Cretaceous, undifferentiated Palegone and Neogene sediments (see stratigraphic column at Fig 3).
Fig 9.
a) 2D interpreted crossline seismic section 891, and b) rose diagram showing the fault system analysis along the N-S and E-W directions.
Fig 10.
a) Depth structural map to top of the Qishn Formation, and b) depth structural map to top of the Nayfa Formation.
Fig 11.
a) Depth structural map to top of the Sab’atayn Formation, and b) depth structural map to top of the Madbi Formation.
Fig 12.
a) Depth structural map to top of the basement reservoir and b) 3D map to the top of the basement reservoir.
The uplifts of the Habban North Horst (HNH) and Habban Central Horst are indicated.
Fig 13.
The cored basement reservoir interval 2370.5–2376.3 m at Habban-1 well.
Good fracture system is indicated at the samples 1, 4 and 5. Sample 1 is completely crushed.
Fig 14.
The compiled neutron-density crossplots of a) Habban-26 well and b) Habban-2A well.
The datapoints of the Lam (blue) and the Meem (red) Members and the basement reservoir (violet) are presented.
Fig 15.
(a& b). Fracture system at exposed basement rocks at Brum area west of Mukalla, Sab’atayn Basin, Yemen.
The pen denotes to the north direction. The white dashed lines indicated fracture directions.
Fig 16.
(a& b). Fracture system identification from the response of well logs at Habban-28 well.
Fig 17.
The resistivity ratio method (RD-RD/RS) for fracture system identification, at Habban-18 well.
The Lam (blue) and Meem Members are located in the non-fractured area below the unity RD/RS line.
Fig 18.
Interpretation of the image log of Habban-35 well.
Fracture analysis and interpretation is indicated at the last track.
Fig 19.
a) Rose diagrams for the fracture/fault system analysis detected from surface lineaments (outcrops), b) core plugs, c) FMI data, and d) interpretation of E-W seismic profiles.
Fig 20.
The petrophysical analysis of the basement reservoir of Habban-29 Well.
Fig 21.
Seismic amplitude and facies analysis of inline seismic section 1335 (see Fig 2 for location).
Gamma ray log (GR, left of wells) and sonic log (right of wells) are used for correlation. A column is provided with the names of the picked reflectors, to the right of the figure. The Paleogene and Neogene strata are undivided and unconformably overlying the Mukalla Formation of the Tawila Group. Tilting and convergent of reflectors is noticed at the Neogene sediments to the west of the seismic section.
Fig 22.
The photo electric absorption factor-density plot of Habban-8 well.
a) A plot of the Lam Member (blue) and Meem Member. b) A plot for the Nayfa Formation (yellow) and Sab’atayn Formation (green).
Fig 23.
Geological cross-section inferred from the interpretation of inline seismic section.
Directions of hydrocarbon migration from the source rock of Madbi Formation into the juxtapose-basement blocks (reservoir) along fault plans are indicated. The thick salts of the Sab’atayn Formation offered a good regional seal.